Rolling mill



0. M. MOWAT.

APPLICATION H E 17,1918. 1,310,2(16, Patented July 15, 1919.

I 2 SHEET'S-QHEET 1.

0. M. MOWAT.

ROlllNG MILL. APPLICATION HLED JULY 5. l9ll- RENEWED DEC- I9!!! 1,310,206. Patented July 15, 1919.

. 2 s'ums-snm 2.

WITNESSES To all whom it may concern:

ottv'nta M. MowA'r, or mnmsronr, PENNSYLVANIA.

ROLLING-MILL.

Application filed July 5, 1917, Serial No. 178,762.

Be it known that I, OLIVER M. Mower, residing at McKeesport, in the county of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvements in Rolling-Mills, of which. lmprovements the following is a specification.

My invention relates to rolling mills, and While in its broader aspects it is applicable to mills for rolling various metal objects, it is particularly applicable to .mills for the hot or cold rolling of tubes.

The object is to provide a mill wherein the forming ofseams or fins u n a tube or other blank being rolled will eliminated or substantially reduced. 'A further object is to provide a tube rolling mill wherein a. tube blank may be simultaneously reduced in diameter and in Wall thickness, or may be reduced in diameter without increasing the thickness of the wall.

In the accompanying sheet of drawings, forming part of my specification, I have illustrated the preferred embodiment of my invention. Figure 1 is a plan view showing. the-preferred eneral arrangement of the mill; Fig.2 .a side elevation of the rolldriving pinions, the plane of-view bein indicated by the line 11-11, Fi 1; Flg. 3

an enlarged sectional view ta en' on the line III-JH, Fig. 1; Fig. 4 a detail sectional view taken on the line Il -IV, 3; Fig. 5 an enlarged combined sectional view of a set of rolls and elevation of the roll housing, the plane of view being indicated by the line V-V, Fig.- 1; Fig. 6 a right end view of the housing asshown in Fig. 5; and Fig. 7 a sectional view taken on the line VIIVII, Fig. 5.

In the rolling of metal articles, the formation of finsthereon is, as is well understood by those skilled in the art, frequently a source of a at deal of difii'culty and annoyance. T ey are formed by the metal of the blank gaining access between the meeting ed es of the rolls adjacent to their operating aces. As rolls are usually constructed, their meeting edges are circular, and form, on the blank being rolled, straight line impressions, so that when the formation of a fin commences there is nothing to break it up and the tendency is for it to increase in size as the blank passes farther between the rolls. I

Specification of Letters Patent.

Patented July 15, 1919.

Renewed December 17, 1918. Serial No. 267,210.

My invention contemplates the overcoming of this difliculty, and to such end, in the practice thereof, I provide rolls inwhich their meeting edgesadjacent to their operating faces are of irregular shape so that the impression of such edges upon a blank is a broken or wavy line. By thus constructing the rolls, the formation of fins will be quickly .broken up.

While the meeting edges of the rolls may be of variousirregular shapes, I preferably provide adjacent rolls with inter'meshing teeth, the edges of such teeth forming a part of the operating or blank-contacting faces of the rolls. The rolls may be adapted to roll differently shaped articles. However, in the illustrative embodiment of my invention, I have shown a group of four rolls constructed to operate upon a tube.

Referring first to Fig. 4, which shows to enlarged scale the arrangement of the rolls and the construction of their operating faces, the rolls 1 and 1 are rotatable on vertical axes and the rolls 2 and 2* on horizontal axes. The sides of each roll are provided with teeth 4 intermeshing with those of adjacent rolls, so that each roll is, in

efl'ect, a two-faced bevel pinion. The operating faces of the rolls are formed by the edges of the teeth and by continuous grooves 5 between the sets of teeth on each roll. Thus the meeting line of the faces of adjacent rolls is irregular, so that if a fin should start to form it will be quickly destroyed rather than continue to the end only necessary to describe that for group A. As shown in Figs. 5, 6 and 7, it comprises a frame or support 6- and carriers 7, 8, and 8, in which, respectively, the rolls 1, 1, Qand 2 are rotatably mounted. The carriers, are clamped to the back of the frame 6 means of suitable bolts 9 projecting through slots in the frame, and each carrier may be adjusted by means of a screw 10. Preferably both the rolls 2 and 2% are directly driven, as by means of horizontal shafts 11 and 11, the rolls 1 and 1 being indirectly driven through the intermeshing teeth 4:-

To the. end that a tubular blank may be passes may all be of circular section.

simultaneously reduced in diameter and in wall thickness, or may be reduced in diameter without increasing the thickness of the wall, the rolls of group B form a smaller diameter pass and are rotated at a greater peripheral speed than those of group A. Thus, as indicated in Fig. 3, the rolls of group B exert a continuous pull upon a blank 12 emerging from the roll group A, thereby drawing the wall of the blank to a less thickness than it would have Were it subjected to no other action than that of the pressure exerted upon it by the rolls. With respect to this, it will be understood that if the blank were subjected to no other action than the pressure of the rolls and if no mandrel were placed within the blank, the thickness of the wall of the blank would be increased.

The driving connections for the rolls are diagrammatically shown in Figs. 1 and 2. As there indicated, the shafts 11 and 11 of the roll group A are suitably connected to wabblers 13 and 13 adapted to be driven by pinions 14 and H, respectively. Referring particularly to the driving connections at the right side of the rolls (the connections on both sides being the same), the pinion 14 is driven through an idler 15", pinion 16, shaft 17", pinion 18*, spur gear 19 and power shaft 20*. The gear ratio is such that the wabblers 21 and 21, driven by the pinions 16 and 16, are rotated more rapidly than the wabblers for the rolls of group A.

In mills for rolling tubes and similar articles, the sections of successive roll passes are usually shaped differently in order to diminish the tendency of squeezing the blank between the adjacent roll faces with the consequent formation of fins. For example, in rod rolling mills, the blankusually passes from a round into an oval pass, and vice versa. By the practice of my invention, successive roll passes may be of the same general shape, without liability of fins being formed. For example, in the present embodiment of my invention, the successive r211 s a result thereof, each set of rolls may, as a tubular blank passes through them, firmly engage a complete circumferential area of the blank so that an even reduction of the thickness of the wall of the blank may be efiected by applying tension to the portion of the blank between the roll passes in the manner described.

According to the provisions of the patent statutes I have described the principle and operation of my invention together with the construction which I now consider to represent the best embodiment thereof.- However, I desire to have it understood that, within the scope of the appended claims, my invention may be practised with other forms of construction than that shown herein.

I claim as my invention:

1. A pair of metal-rolling rolls provided adjacent to their operating faces with discontinuous meeting edges adapted to interrupt the continuity of a fin formed upon a blank while being rolled.

2. A pair of metal-rolling rolls provided with intermeshing teeth, the metal-contacting roll faces being formed in part by the overlapping edges of said teeth.

3. A tube-rolling mill including a pair of rolls provided with intermeshing teeth. the tube-contacting roll faces being formed in part by the overlapping edges of said teeth.

4. A tube-rolling mill including two pairs of rolls having their axes substantially at right angles to each other and provided with intermeshing teeth, the tube contacting roll faces being formed in part by the overlapping edges of said teeth.

5. In a tube rolling mill, the combination,

of two sets of rolls constituting consecutive roll passes, the rolls of each set being provided with intermeshing teeth, the edges of which constitute a part of the tube-contacting r011 faces, and means for driving said sets of rolls at different peripheral speeds.

6. In a tube rolling mill, the combination of two sets of rolls constituting consecutive roll passes of circular section, the adjacent rolls of said sets of rolls being provided adjacent to their operating faces with discontinuous meeting faces adapted to interrupt the continuity of a fin formed upon a blank while being rolled, and means for driving each set of rolis, the rolls forming the second pass being driven at a peripheral speed substantially greater than those of the first pass whereby a blank becomes stretched between said sets of rolls.

In testimony whereof I have hereunto set my hand.

OLIVER M. MOIVAT.

Witnesses:

PAUL N. Cmrcrmow, FRANCIS J. TOMASSON. 

